class A:
    def __init__(self):
        print("A")
class B(A):
    def __init__(self):
        print("B")
        super().__init__()
class C(A):
    def __init__(self):
        print("C")
        super().__init__()
class D(B,C):
    def __init__(self):
        print("D")
        super().__init__()
if __name__ == '__main__':
    print(D.mro())
    print(D())